3. Preserving a food prevente microorganisms from changing the foods,s original Characteristics, such as its appearence, smell or taste, in order to keep the Food safe to eat for a longer period of time.
3.1 Metidos of food preservación
- Methods that use low temperaturas.
Are used to prevent the growth of microorganisms that thrive at Room temperature. Refrigeration involves keeping foods at temperatures between 0c and 4c and freezing consiste oíd storing foods at or below -18c
- Methods that use high temperatures
Sterilisation or Uht processing is a processing is a process in Which food is heated at a temperature of 135c for two or three seconds in order To destruyo all microorganism. This metido allows products to be stored for a Very long time.
During pasteurisation food is heated to between 64c and 75c for a Short time and then colee quickly.
Dehydration or drying consiste of using a heat source to remove The water contamine in foods. Food can be completely dehydrated or partially Dehydrated.
-Methods that use preservatives
Subtances known as preservatives can also be added to foods to Prevent the growth of microoganisms, such as salt, vinegar, certain substancies In the smoke produced by burning wood and artifial chemical additives.
3.2 Food aditivos
Food additives are substancies that are added to a food to Preserve its favour, smell, colour, etc. To change its characteristics or to Keep it safe to eat for a longer period of time.
-Food colourings, also called colours, serve an aesthetic and physicholical Pùrpose, as they make the food more appealipng to us, like turmeric is used to Give foods a yellow colour.
- Preservatives, prevent the growth of microorganismos, delaying Food spoilage, like the sorbic acid.
-Antioxidants, prevent foods from oxidising, like ascorbic acid.
- Textuire modifiers like thickeners are added to foods to change Their consistency, such as latinate.
- Flavour enhancers, these subtances do not provide a flavour of Their own, but racher enhance the flavour of the food like the glutamate.